Background

Aberdeen International Business Park is a large commercial development located adjacent to Aberdeen International Airport, on the principal link road between the airport and the Aberdeen Western Peripheral Route / A96.

The first phase of the development covers 31,000m² within a wider 16.2 hectare site, delivering high quality office accommodation alongside restaurant, leisure and future hotel facilities for the international business community in Aberdeen.

Given the site’s proximity to sensitive water environments, including the River Dee, a protected salmon river, the drainage strategy was required to meet strict planning and pollutant removal criteria set by the Scottish Environment Protection Agency (SEPA).

The challenge

SEPA required the surface water drainage strategy to deliver high levels of treatment to protect downstream water quality.

Key challenges included:

  • Meeting stringent SuDS and pollution control requirements
  • Protecting the Green Burn and ultimately the River Dee
  • Delivering multiple stages of treatment within a restricted footprint
  • Managing runoff from large impermeable areas, including a multi storey car park
  • Adapting SuDS design to a relatively flat site with a rerouted local watercourse

SEPA required two levels of pollution control in parts of the treatment train, limiting the suitability of more traditional, space hungry SuDS features.

The solution

Consultants Mott MacDonald specified a combination of Marshalls and Hydro International systems, selecting compact filtration and biofiltration technologies to form a comprehensive SuDS treatment train.

Key elements included:

  • Up Flo™ filtration units installed within precast concrete manholes to treat runoff from the car park. Up Flo™ combines sedimentation, screening and fluidised bed filtration in a single device, removing fine sediments, hydrocarbons and other pollutants.
  • BioCell™ biofiltration units, which visually resemble tree or shrub planters at surface level. Beneath the surface, each unit contains a precast concrete chamber with enhanced mulch and a specialist soil filter medium, delivering consistent and effective surface water treatment.

These systems were integrated alongside other SuDS components, including filter strips, permeable pavement, filter trenches, soakaways and an attenuation tank beneath the car park, creating a robust mixed drainage solution across the site.

Runoff is ultimately discharged into the Green Burn, from where it flows into the River Dee, following the required levels of treatment.

The outcome

TThe completed SuDS scheme delivered a best practice drainage solution capable of meeting SEPA’s stringent environmental standards while accommodating the spatial constraints of a major commercial development.

Nick Watson, Project Engineer at Mott MacDonald, commented:

“SEPA required two levels of pollution control in the drainage treatment train for some areas of the site. The six BioCell units are installed in a landscaped courtyard garden around three linked four storey commercial blocks.”

He added:

“Space constraints meant that finding small footprint solutions that could achieve high treatment levels was limited. There are occasions where more natural engineering approaches are less suitable due to a lack of space, and having an option like Up Flo can be very useful.”

The result is a visually integrated, high performance SuDS scheme that protects sensitive receiving waters while supporting the long term success of a strategically important business park.